I just installed a comfort aire 80% 120,000 BTU furnace. When I started the furnace inducer fan started the electronic ignitor started 10 seconds later and successfully lit the burners on the first try. They burn solid blue but go out within 10 seconds of the ignitor going off. The indicator light never turns from a solid green so no diagnostics from there. The furnace cycles three times without success. Brand new so I don't think it could be the flame sensor. Any help would be greatly appreciated.

Flame sensor wiring, flame sensor position, flame detect circuitry faulty, switch the wires on the 24 V secondary (polarity error), Measure the flame sensor current in uA or a bad ground.

I'd start by switching the secondary.